/*
- * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
- *
- * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the
- * License may not be used to create, or enable the creation or
- * redistribution of, unlawful or unlicensed copies of an Apple operating
- * system, or to circumvent, violate, or enable the circumvention or
- * violation of, any terms of an Apple operating system software license
- * agreement.
+ * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.
*
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
* limitations under the License.
*
- * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
+
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/fcntl.h>
#include <string.h>
#include <miscfs/devfs/devfs.h>
-#include <kern/lock.h>
+#include <kern/locks.h>
+#include <kern/clock.h>
#include <sys/time.h>
#include <sys/malloc.h>
+#include <sys/sysproto.h>
#include <sys/uio_internal.h>
#include <dev/random/randomdev.h>
-#include <dev/random/YarrowCoreLib/include/yarrow.h>
-#include <crypto/sha1.h>
+
+#include <libkern/OSByteOrder.h>
+#include <libkern/OSAtomic.h>
+
+#include <mach/mach_time.h>
#define RANDOM_MAJOR -1 /* let the kernel pick the device number */
+#define RANDOM_MINOR 0
+#define URANDOM_MINOR 1
d_ioctl_t random_ioctl;
*/
static struct cdevsw random_cdevsw =
{
- random_open, /* open */
- random_close, /* close */
- random_read, /* read */
- random_write, /* write */
- random_ioctl, /* ioctl */
+ random_open, /* open */
+ random_close, /* close */
+ random_read, /* read */
+ random_write, /* write */
+ random_ioctl, /* ioctl */
(stop_fcn_t *)nulldev, /* stop */
(reset_fcn_t *)nulldev, /* reset */
- NULL, /* tty's */
- eno_select, /* select */
- eno_mmap, /* mmap */
- eno_strat, /* strategy */
- eno_getc, /* getc */
- eno_putc, /* putc */
- 0 /* type */
+ NULL, /* tty's */
+ eno_select, /* select */
+ eno_mmap, /* mmap */
+ eno_strat, /* strategy */
+ eno_getc, /* getc */
+ eno_putc, /* putc */
+ 0 /* type */
};
-/* Used to detect whether we've already been initialized */
-static int gRandomInstalled = 0;
-static PrngRef gPrngRef;
-static int gRandomError = 1;
-static mutex_t *gYarrowMutex = 0;
-
-#define RESEED_TICKS 50 /* how long a reseed operation can take */
-
-
-enum {kBSizeInBits = 160}; // MUST be a multiple of 32!!!
-enum {kBSizeInBytes = kBSizeInBits / 8};
-typedef u_int32_t BlockWord;
-enum {kWordSizeInBits = 32};
-enum {kBSize = 5};
-typedef BlockWord Block[kBSize];
-
-/* define prototypes to keep the compiler happy... */
-
-void add_blocks(Block a, Block b, BlockWord carry);
-void fips_initialize(void);
-void random_block(Block b);
-
-/*
- * Get 120 bits from yarrow
- */
-
-/*
- * add block b to block a
- */
-void
-add_blocks(Block a, Block b, BlockWord carry)
-{
- int i = kBSize;
- while (--i >= 0)
- {
- u_int64_t c = (u_int64_t)carry +
- (u_int64_t)a[i] +
- (u_int64_t)b[i];
- a[i] = c & ((1LL << kWordSizeInBits) - 1);
- carry = c >> kWordSizeInBits;
- }
-}
-
-
-
-struct sha1_ctxt g_sha1_ctx;
-char zeros[(512 - kBSizeInBits) / 8];
-Block g_xkey;
-Block g_random_data;
-int g_bytes_used;
-
-/*
- * Setup for fips compliance
- */
-
-/*
- * get a random block of data per fips 186-2
- */
-void
-random_block(Block b)
-{
- // do one iteration
- Block xSeed;
- prngOutput (gPrngRef, (BYTE*) &xSeed, sizeof (xSeed));
-
- // add the seed to the previous value of g_xkey
- add_blocks (g_xkey, xSeed, 0);
-
- // compute "G"
- SHA1Update (&g_sha1_ctx, (const u_int8_t *) &g_xkey, sizeof (g_xkey));
-
- // add zeros to fill the internal SHA-1 buffer
- SHA1Update (&g_sha1_ctx, (const u_int8_t *)zeros, sizeof (zeros));
-
- // write the resulting block
- memmove(b, g_sha1_ctx.h.b8, sizeof (Block));
-
- // fix up the next value of g_xkey
- add_blocks (g_xkey, b, 1);
-}
-
-/*
- *Initialize ONLY the Yarrow generator.
- */
-void
-PreliminarySetup(void)
-{
- prng_error_status perr;
- struct timeval tt;
- char buffer [16];
-
- /* create a Yarrow object */
- perr = prngInitialize(&gPrngRef);
- if (perr != 0) {
- printf ("Couldn't initialize Yarrow, /dev/random will not work.\n");
- return;
- }
-
- /* clear the error flag, reads and write should then work */
- gRandomError = 0;
-
- /* get a little non-deterministic data as an initial seed. */
- microtime(&tt);
-
- /*
- * So how much of the system clock is entropic?
- * It's hard to say, but assume that at least the
- * least significant byte of a 64 bit structure
- * is entropic. It's probably more, how can you figure
- * the exact time the user turned the computer on, for example.
- */
- perr = prngInput(gPrngRef, (BYTE*) &tt, sizeof (tt), SYSTEM_SOURCE, 8);
- if (perr != 0) {
- /* an error, complain */
- printf ("Couldn't seed Yarrow.\n");
- return;
- }
-
- /* turn the data around */
- perr = prngOutput(gPrngRef, (BYTE*)buffer, sizeof (buffer));
-
- /* and scramble it some more */
- perr = prngForceReseed(gPrngRef, RESEED_TICKS);
-
- /* make a mutex to control access */
- gYarrowMutex = mutex_alloc(0);
-
- fips_initialize ();
-}
-
-void
-fips_initialize(void)
-{
- /* Read the initial value of g_xkey from yarrow */
- prngOutput (gPrngRef, (BYTE*) &g_xkey, sizeof (g_xkey));
-
- /* initialize our SHA1 generator */
- SHA1Init (&g_sha1_ctx);
-
- /* other initializations */
- memset (zeros, 0, sizeof (zeros));
- g_bytes_used = 0;
- random_block(g_random_data);
-}
/*
* Called to initialize our device,
{
int ret;
- if (gRandomInstalled)
- return;
-
- /* install us in the file system */
- gRandomInstalled = 1;
-
- /* setup yarrow and the mutex */
- PreliminarySetup();
-
ret = cdevsw_add(RANDOM_MAJOR, &random_cdevsw);
if (ret < 0) {
- printf("random_init: failed to allocate a major number!\n");
- gRandomInstalled = 0;
- return;
+ panic("random_init: failed to allocate a major number!");
}
- devfs_make_node(makedev (ret, 0), DEVFS_CHAR,
- UID_ROOT, GID_WHEEL, 0666, "random", 0);
+ devfs_make_node(makedev(ret, RANDOM_MINOR), DEVFS_CHAR,
+ UID_ROOT, GID_WHEEL, 0666, "random", 0);
/*
- * also make urandom
+ * also make urandom
* (which is exactly the same thing in our context)
*/
- devfs_make_node(makedev (ret, 1), DEVFS_CHAR,
- UID_ROOT, GID_WHEEL, 0666, "urandom", 0);
+ devfs_make_node(makedev(ret, URANDOM_MINOR), DEVFS_CHAR,
+ UID_ROOT, GID_WHEEL, 0666, "urandom", 0);
}
int
-random_ioctl( __unused dev_t dev, u_long cmd, __unused caddr_t data,
- __unused int flag, __unused struct proc *p )
+random_ioctl( __unused dev_t dev, u_long cmd, __unused caddr_t data,
+ __unused int flag, __unused struct proc *p )
{
switch (cmd) {
case FIONBIO:
return ENODEV;
}
- return (0);
+ return 0;
}
/*
* Open the device. Make sure init happened, and make sure the caller is
* authorized.
*/
-
+
int
random_open(__unused dev_t dev, int flags, __unused int devtype, __unused struct proc *p)
{
- if (gRandomError != 0) {
- /* forget it, yarrow didn't come up */
- return (ENOTSUP);
- }
-
/*
* if we are being opened for write,
* make sure that we have privledges do so
*/
if (flags & FWRITE) {
- if (securelevel >= 2)
- return (EPERM);
+ if (securelevel >= 2) {
+ return EPERM;
+ }
#ifndef __APPLE__
- if ((securelevel >= 1) && proc_suser(p))
- return (EPERM);
-#endif /* !__APPLE__ */
+ if ((securelevel >= 1) && proc_suser(p)) {
+ return EPERM;
+ }
+#endif /* !__APPLE__ */
}
- return (0);
+ return 0;
}
/*
* close the device.
*/
-
+
int
random_close(__unused dev_t dev, __unused int flags, __unused int mode, __unused struct proc *p)
{
- return (0);
+ return 0;
}
* prng.
*/
int
-random_write (__unused dev_t dev, struct uio *uio, __unused int ioflag)
+random_write(dev_t dev, struct uio *uio, __unused int ioflag)
{
- int retCode = 0;
- char rdBuffer[256];
-
- if (gRandomError != 0) {
- return (ENOTSUP);
- }
-
- /* get control of the Yarrow instance, Yarrow is NOT thread safe */
- mutex_lock(gYarrowMutex);
-
- /* Security server is sending us entropy */
-
- while (uio_resid(uio) > 0 && retCode == 0) {
- /* get the user's data */
- // LP64todo - fix this! uio_resid may be 64-bit value
- int bytesToInput = min(uio_resid(uio), sizeof (rdBuffer));
- retCode = uiomove(rdBuffer, bytesToInput, uio);
- if (retCode != 0)
- goto /*ugh*/ error_exit;
-
- /* put it in Yarrow */
- if (prngInput(gPrngRef, (BYTE*)rdBuffer,
- bytesToInput, SYSTEM_SOURCE,
- bytesToInput * 8) != 0) {
- retCode = EIO;
- goto error_exit;
- }
- }
-
- /* force a reseed */
- if (prngForceReseed(gPrngRef, RESEED_TICKS) != 0) {
- retCode = EIO;
- goto error_exit;
- }
-
- /* retCode should be 0 at this point */
-
-error_exit: /* do this to make sure the mutex unlocks. */
- mutex_unlock(gYarrowMutex);
- return (retCode);
+ int retCode = 0;
+ char rdBuffer[256];
+
+ if (minor(dev) != RANDOM_MINOR) {
+ return EPERM;
+ }
+
+ /* Security server is sending us entropy */
+
+ while (uio_resid(uio) > 0 && retCode == 0) {
+ /* get the user's data */
+ int bytesToInput = MIN(uio_resid(uio),
+ (user_ssize_t) sizeof(rdBuffer));
+ retCode = uiomove(rdBuffer, bytesToInput, uio);
+ if (retCode != 0) {
+ break;
+ }
+ retCode = write_random(rdBuffer, bytesToInput);
+ if (retCode != 0) {
+ break;
+ }
+ }
+
+ return retCode;
}
/*
* return data to the caller. Results unpredictable.
- */
-int random_read(__unused dev_t dev, struct uio *uio, __unused int ioflag)
+ */
+int
+random_read(__unused dev_t dev, struct uio *uio, __unused int ioflag)
{
- int retCode = 0;
-
- if (gRandomError != 0)
- return (ENOTSUP);
-
- /* lock down the mutex */
- mutex_lock(gYarrowMutex);
-
- int bytes_remaining = uio_resid(uio);
- while (bytes_remaining > 0 && retCode == 0) {
- /* get the user's data */
- int bytes_to_read = 0;
-
- int bytes_available = kBSizeInBytes - g_bytes_used;
- if (bytes_available == 0)
- {
- random_block(g_random_data);
- g_bytes_used = 0;
- bytes_available = kBSizeInBytes;
+ int retCode = 0;
+ char buffer[512];
+
+ user_ssize_t bytes_remaining = uio_resid(uio);
+ while (bytes_remaining > 0 && retCode == 0) {
+ int bytesToRead = MIN(bytes_remaining,
+ (user_ssize_t) sizeof(buffer));
+ read_random(buffer, bytesToRead);
+
+ retCode = uiomove(buffer, bytesToRead, uio);
+ if (retCode != 0) {
+ break;
}
-
- bytes_to_read = min (bytes_remaining, bytes_available);
-
- retCode = uiomove(((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read, uio);
- g_bytes_used += bytes_to_read;
-
- if (retCode != 0)
- goto error_exit;
-
+
bytes_remaining = uio_resid(uio);
- }
-
- retCode = 0;
-
-error_exit:
- mutex_unlock(gYarrowMutex);
- return retCode;
-}
+ }
-/* export good random numbers to the rest of the kernel */
-void
-read_random(void* buffer, u_int numbytes)
-{
- if (gYarrowMutex == 0) { /* are we initialized? */
- PreliminarySetup ();
- }
-
- mutex_lock(gYarrowMutex);
-
- int bytes_remaining = numbytes;
- while (bytes_remaining > 0) {
- int bytes_to_read = min(bytes_remaining, kBSizeInBytes - g_bytes_used);
- if (bytes_to_read == 0)
- {
- random_block(g_random_data);
- g_bytes_used = 0;
- bytes_to_read = min(bytes_remaining, kBSizeInBytes);
- }
-
- memmove (buffer, ((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read);
- g_bytes_used += bytes_to_read;
-
- bytes_remaining -= bytes_to_read;
- }
-
- mutex_unlock(gYarrowMutex);
+ return retCode;
}
/*
- * Return an unsigned long pseudo-random number.
+ * Return an u_int32_t pseudo-random number.
*/
-u_long
+u_int32_t
RandomULong(void)
{
- u_long buf;
- read_random(&buf, sizeof (buf));
- return (buf);
+ u_int32_t buf;
+ read_random(&buf, sizeof(buf));
+ return buf;
}
+
+int
+getentropy(__unused struct proc * p, struct getentropy_args *gap, __unused int * ret)
+{
+ user_addr_t user_addr;
+ uint32_t user_size;
+ char buffer[256];
+
+ user_addr = (vm_map_offset_t)gap->buffer;
+ user_size = gap->size;
+ /* Can't request more than 256 random bytes
+ * at once. Complying with openbsd getentropy()
+ */
+ if (user_size > sizeof(buffer)) {
+ return EINVAL;
+ }
+ read_random(buffer, user_size);
+ return copyout(buffer, user_addr, user_size);
+}
projects / apple / xnu.git / blobdiff